1. Field of the Invention
The present invention relates to a shorts and continuity tester, and more specifically to one which utilizes an ionic solution to measure the electrical characteristics of various portions of a multilayered printed circuit board or ceramic substrate.
2. Description of the Prior Art
A multipoint "bed of nails" type fixture has been one way in which shorts and continuity checking has been performed on multilayered printed circuit boards and ceramic substrates. With such a structure each "nail" is connected to at least one other "nail" by way of an electrical measuring instrument such as an ohmmeter. As the "bed of nails" fixture is positioned over the circuit board to be checked, the resistance value is measured between the two "nails" which come into contact with two points on the circuit board. The measured resistance value is then compared to the resistance value expected between those two points in the circuit. A difference between the two values is an indication of a malfunction which necessitates further investigation.
One disadvantage of this type of fixture is that it requires contact with all points on the circuit board under test. Furthermore, as the state of the art advances in the miniaturization of printed circuit boards, their conductor paths can be printed closer and closer together. As the conductor paths are fabricated closer together, it is physically more difficult to configure a "bed of nail" type testing fixture that will operate reliably due to the close proximity required for adjacent "nail" probes.
Accordingly, it is an object of the present invention to provide a relatively simple, lower cost and more reliable means in which to accomplish electrical measurements on printed circuit boards.
It is a further object of the invention to eliminate the long turn around time required to design and construct prior art test fixtures.